A difficult obstacle associated with the exploration and production of oil and gas is management of significant ocean currents. These currents can produce vortex-induced vibration (VIV) and/or large deflections of tubulars associated with drilling and production. VIV can cause substantial fatigue damage to the tubular or cause suspension of drilling due to increased deflections. Both helical strakes and fairings can provide sufficient VIV suppression, but can be slow and unsafe to install.
Helical strakes are typically banded onto the underlying tubular. Banding allows for a fairly large amount of compressive force to be transmitted through the helical strake to the underlying tubular so that the helical strake does not slide axially (e.g. due to gravity) due to friction.
A problem associated with banded helical strakes is that the bands are expensive. Another problem with banded helical strakes is that they are slow to install. Still another problem associated with banded helical strakes is that the bands are unable to provide sufficient tension when the underlying tubular diameter is too large or if the coefficient of friction between the strake and the underlying tubular is too small.
One important consideration for helical strakes is that the tubular diameter can vary along the tubular length. This can make determination of the friction between the helical strake and the underlying tubular both uncertain and difficult to manage.